1. Field of the Invention
The present invention relates to a utility vehicle including a vehicle body frame including a main frame to which an engine is mounted.
2. Description of the Related Art
Japanese Laid-Open Patent Application Publication No. 2007-276703 discloses an exemplary conventional utility vehicle. In this utility vehicle, an engine is mounted to a main frame constituting a vehicle body frame, and a seat on which a passenger can be seated is fastened to a part of the main frame. In the utility vehicle, the main frame is entirely constructed of rectangular pipes with rectangular cross-sections. Therefore, the main frame has a high stiffness against an engine load applied to the main frame in a vertical direction or an external load applied to the main frame in a forward and rearward direction. This makes it possible to prevent the main frame from being deformed by the engine load, the external load, etc.
Round pipes with circular cross-sections are used for a cabin frame (ROPS), but not for the main frame. For this reason, in a state where the cabin frame (ROPS) is detached, curved lines of the round pipes do not appear in an external shape of the utility vehicle, and the external design appearance is undesirable. Therefore, there is a need for improvement of external design appearance of the utility vehicle in a state where the cabin frame (ROPS) is detached, while maintaining a high stiffness of the main frame in the vertical direction and in the forward and rearward direction.